Gain and phase mismatches between an in-phase (i.e., I) path and a quadrature (i.e., Q) path of a quadrature transmitter (i.e., I/Q mismatch) may result in an output having one or more undesired frequencies, images and/or sidebands in addition to a desired signal. Such undesired frequencies, images and/or sidebands can cause a degradation and/or distortion of the desired signal (i.e., I/Q distortion). For example, an undesired frequency, image and/or sideband may cause a receiver error, and/or to violate an emission mask that specifies allowed transmitted power at particular frequencies. Typically, the analog portions of a quadrature transmitter (e.g., an analog modulator) contribute the majority of the I/Q mismatch. In some circumstances the I/Q mismatch may vary over time with, for example, ambient temperature. While analog circuit induced I/Q mismatch may be digitally corrected by, for example, a digital signal processor or other hardware prior to conversion to the analog domain, digital correction requires access to digital transmit signals that may not be available to the engineer designing, tuning and/or testing a quadrature transmitter.